This invention relates to an exposure apparatus and a method for lithographically transferring a mask having a pattern onto a photosensitive substrate through a projection optical system.
Conventional exposure apparatuses are generally arranged, for monitoring the state of operation of the apparatus, so that the state of sequence is continuously monitored by using software or hardware. For example, sequence members are assigned to processes beforehand and a corresponding sequence number is displayed on the exposure apparatus, whereby the state of operation of the apparatus is informed to an operator. Further, error numbers corresponding to disorders are assigned beforehand and, like the sequence numbers described above, an error number corresponding to a disorder that has occurred is displayed on the exposure apparatus, whereby the disorder is notified to the operator.
When plural exposure apparatuses are controlled through a network, generally, such a sequence number or an error number is notified from the exposure apparatus to a host computer. The host computer analyzes the received sequence number or error number and controls the state of operation of each apparatus.
In order to meet production of new devices or enhancement of precision, addition or modification of functions or units is made in exposure apparatuses. In such addition or modification of functions, it is necessary to incorporate additional sequence numbers or error numbers corresponding to added sequences or units for the function addition or modification. Also, in a network controlled system, the system itself has to be modified to meet the addition or modification of the function of each exposure apparatus.
Semiconductor devices are becoming smaller, and higher precision is required. Higher productivity is also required in order that new devices can be put on the market quickly. For these reasons, recently, the addition or modification of functions of an exposure apparatus is made frequently. This necessitates a complicated structure or system changing works in exposure apparatus manufacturers or semiconductor chip manufacturers, which burdens an increasing load to these manufacturers. On the other hand, in exposure apparatuses, periodic maintenance operations are made to keep the precision high. If an error occurs in a unit, the maintenance operation cannot be initiated until the error number analysis is completed. Thus, the operation of the exposure apparatus is discontinued in that period, and the productivity is, therefore, lowered.
It is an object of the present invention to provide an exposure apparatus, an exposure method and/or a device manufacturing method by which, on the basis of monitoring vibration information of the exposure apparatus, calculation of a maintenance time of the apparatus or detection of an error in the apparatus can be done easily and by which any addition or modification of a function in the apparatus can be met easily.
In accordance with an aspect of the present invention, there is provided an exposure apparatus for exposing a photosensitive substrate to a mask having a pattern through a projection optical system, comprising: means for detecting vibration information related to said apparatus; and means for analyzing the detected vibration information.
In accordance with another aspect of the present invention, there is provided an exposure apparatus for exposing a photosensitive substrate to a mask having a pattern through a projection optical system, comprising: means for detecting vibration information related to said apparatus; and means for storing the detected vibration information.
In accordance with a further aspect of the present invention, there is provided an exposure method to be used with an exposure apparatus as recited above, wherein the state of operation of the apparatus is controlled on the basis of the detected vibration information.
In accordance with a yet further aspect of the present invention, there is provided a device manufacturing method for producing a device by use of an exposure apparatus as recited above.
These and other objects, features and advantages of the present invention will become more apparent upon a consideration of the following description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.